Lower Limb Ischemia-reperfusion Research Articles

Targeting Mitochondrial Dynamics during Lower-Limb Ischemia Reperfusion in Young and Old Mice: Effect of Mitochondrial Fission Inhibitor-1 (mDivi-1).

Peripheral arterial disease (PAD) strikes more than 200 million people worldwide and has a severe prognosis by potentially leading to limb amputation and/or death, particularly in older patients. Skeletal muscle mitochondrial dysfunctions and oxidative stress play major roles in this disease in relation with ischemia-reperfusion (IR) cycles. Mitochondrial dynamics through impairment of fission-fusion balance may contribute to skeletal muscle pathophysiology, but no data were reported in the setting of lower-limb IR despite the need for new therapeutic options. We, therefore, investigated the potential protective effect of mitochondrial division inhibitor-1 (mDivi-1; 50 mg/kg) in young (23 weeks) and old (83 weeks) mice submitted to two-hour ischemia followed by two-hour reperfusion on systemic lactate, muscle mitochondrial respiration and calcium retention capacity, and on transcripts specific for oxidative stress and mitochondrial dynamics. At the systemic levels, an IR-related increase in circulating lactate was still major despite mDivi-1 use (+305.9% p < 0.0001, and +269.4% p < 0.0001 in young and old mice, respectively). Further, IR-induced skeletal muscle mitochondrial dysfunctions (more severely impaired mitochondrial respiration in old mice (OXPHOS CI state, -68.2% p < 0.0001 and -84.9% p < 0.0001 in 23- and 83-week mice) and reduced calcium retention capacity (-46.1% p < 0.001 and -48.2% p = 0.09, respectively) were not corrected by mDivi-1 preconditioning, whatever the age. Further, mDivi-1 treatment did not oppose superoxide anion production (+71.4% p < 0.0001 and +37.5% p < 0.05, respectively). At the transcript level, markers of antioxidant enzymes (SOD 1, SOD 2, catalase, and GPx) and fission markers (Drp1, Fis) remained unchanged or tended to be decreased in the ischemic leg. Fusion markers such as mitofusin 1 or 2 decreased significantly after IR in both groups. In conclusion, aging enhanced the deleterious effects or IR on muscle mitochondrial respiration, and in this setting of lower-limb IR, mDivi-1 failed to protect the skeletal muscle both in young and old mice.

Effects of sevoflurane and fullerenol C60 on lower limb ischemia-reperfusion injury in streptozocin-induced diabetic mice.

Ischemia-reperfusion injury (IRI) poses a significant challenge for physicians, necessitating the management of cell damage and the preservation of organ functions. Various surgical procedures, such as vascular surgery on extremities, temporary cross-clamping of the abdominal aorta in aortic surgery, and the use of a tourniquet in extremity surgeries, may induce lower limb IRI. The susceptibility to IRI is heightened in individuals with diabetes. This study aimed to investigate the effects of fullerenol C60 and sevoflurane on mouse muscle tissue in a lower limb IRI model and to assess their potential in preventing complications arising from ischemia-reperfusion in mice with streptozocin-induced diabetes. A total of 36 adult Swiss albino mice were randomly divided into six groups, each consisting of six mice: control group (group C), diabetes group (group D), diabetes-ischemia/reperfusion group (group DIR), diabetes-ischemia/reperfusion-fullerenol C60 group (group DIR-FC60), diabetes-ischemia/reperfusion-sevoflurane group (group DIR-S), and diabetes-ischemia/reperfusion-sevoflurane-fullerenol C60 group (DIR-S-FC60). Streptozocin (55 mg/kg) was intraperitoneally administered to induce diabetes in the relevant groups, with mice displaying blood glucose levels of 250 mg/dL or higher at 72 h were considered diabetic. After 4 weeks, all groups underwent laparotomy under anesthesia. In DIR-FC60 and DIR-S-FC60 groups, fullerenol C60 (100 mg/kg) was intraperitoneally administrated 30 min before the ischemia period. Sevoflurane, delivered in 100% oxygen at a rate of 2.3% and 4 L/min, was administered during the ischemia period in DIR-S and DIR-S-FC60 groups. In the IR groups, a microvascular clamp was placed on the infrarenal abdominal aorta for 120 min during the ischemia period, followed by the removal of the clamp and a 120-min reperfusion period. At the end of the reperfusion, gastrocnemius muscle tissues were removed for histopathological and biochemical parameter examinations. Histopathological examination revealed a significant reduction in the disorganization and degeneration of muscle cells in the DIR-S-FC60 group compared to the DIR group (p = 0.041). Inflammatory cell infiltration was notably lower in the DIR-S, DIR-FC60, and DIR-S-FC60 groups than in the DIR group (p = 0.031, p = 0.011, and p = 0.013, respectively). The total damage scores in the DIR-FC60 and DIR-S-FC60 groups were significantly lower than in the DIR group (p = 0.018 and p = 0.008, respectively). Furthermore, the levels of malondialdehyde (MDA) in the DIR-S, DIR-FC60, and DIR-S-FC60 groups were significantly lower than in the DIR group (p < 0.001, p < 0.001, and p < 0.001, respectively). Catalase (CAT) enzyme activity in the DIR-S, DIR-FC60, and DIR-S-FC60 groups was higher than in the DIR group (p = 0.001, p = 0.014, and p < 0.001, respectively). Superoxide dismutase (SOD) enzyme activity in the DIR-FC60 and DIR-S-FC60 groups was also higher than in the DIR group (p < 0.001 and p = 0.001, respectively). Our findings indicate that administering fullerenol C60 30 min prior to ischemia in diabetic mice, in combination with sevoflurane, led to a reduction in oxidative stress and the correction of IR-related damage in muscle tissue histopathology. We believe that the administration of fullerenol C60 before IR, coupled with sevoflurane administration during IR, exerts a protective effect in mice.

Effect of miR-206 on lower limb ischemia–reperfusion injury in rat and its mechanism

Lower limb ischemia–reperfusion is a common pathological process during clinical surgery. Because lower limb ischemia–reperfusion usually aggravates ischemia-induced skeletal muscle tissue injury after lower limb ischemia–reperfusion, it also causes remote organ heart, intestine, liver, lung and other injuries, and there is no effective clinical treatment for lower limb ischemia–reperfusion injury, so it is urgent to study its injury mechanism. In this study, the rat model of lower limb ischemia–reperfusion was established by clamping the femoral artery with microarterial clips, and the wall destruction such as intimal injury, cell edema, collagen degeneration, neutrophil infiltration, and elastic fiberboard injury of the femoral artery wall was detected. The expression of inflammatory factors was detected by immunohistochemistry. miR-206 preconditioning was used to observe the expression of inflammatory factors, redox status and apoptosis in the vascular wall of rats after acute limb ischemia–reperfusion. Our findings suggest that vascular endothelial cell edema increases, wall thickening, neutrophil infiltration, and elastic fiber layer damage during IRI. Inflammatory factor expression was increased in femoral artery tissue, and miR-206 expression levels were significantly down-regulated. Further studies have found that miR-206 attenuates lower limb IRI by regulating the effects of phase inflammatory factors. In this study, we investigated the effect of miR-206 on inflammatory factors and its possible role in the development of lower limb IRI, providing new research ideas for the regulatory mechanism of lower limb IRI, and providing a certain theoretical basis for the treatment of lower limb ischemia–reperfusion injury after surgery or endovascular intervention.

Mitochondrial transplantation reduces lower limb ischemia-reperfusion injury by increasing skeletal muscle energy and adipocyte browning

Recent studies have shown that mitochondrial transplantation can repair lower limb IRI, but the underlying mechanism of the repair effect remains unclear. In this study, we found that in addition to being taken up by skeletal muscle cells, human umbilical cord mesenchymal stem cells (hMSCs)-derived mitochondria were also taken up by adipocytes, which was accompanied by an increase in optic atrophy 1 (OPA1) and uncoupling protein 1. Transplantation of hMSCs-derived mitochondria could not only supplement the original damaged mitochondrial function of skeletal muscle, but also promote adipocyte browning by increasing the expression of OPA1. In this process, mitochondrial transplantation can reduce cell apoptosis and repair muscle tissue, which promotes the recovery of motor function invivo. To the best of our knowledge, there is no study on the therapeutic mechanism of mitochondrial transplantation from this perspective, which could provide a theoretical basis.

The effect of Edaravone on lung injury after lower limb ischemiareperfusion in a rat model: Biochemical and histopathological insights

Aim: Lower limb ischemia/reperfusion leads to distant organ dysfunction, notably affecting the lungs, resulting in respiratory failure and significant morbidity and mortality. Edaravone is a new free radical scavenger and has attracted the attention of researchers. This study aims to examine edaravone's influence on lung injury arising from lower limb ischemia-reperfusion. Material and Methods: Forty male Wistar rats were categorized into groups: Sham, Ischemia/Reperfusion (IR), Solvent, and Edaravone. The infrarenal abdominal aorta was clamped for 120 minutes and then reperfused for another 120 minutes. Edaravone was administered 30 minutes before the ischemic event. Then we analyzed serum and lung tissue samples for malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), and nitric oxide (NO) levels. Furthermore, a thorough histopathological assessment was conducted. Results: In the IR group, edaravone notably reduced serum and lung MDA levels. While significant differences in serum SOD and NO levels existed between the IR and edaravone groups, similar differences were not found in the lung tissue samples. There appeared to be no significant impact of edaravone on serum and lung GPx levels. The histopathological investigation revealed that the lung injury score was significantly higher in the IR group compared to the control group, a difference mitigated by edaravone treatment. Conclusion: Our findings suggest that edaravone mitigates lower limb ischemia-reperfusion-induced lung injury, both biochemically and histopathologically. Our findings imply the potential utility of this agent in the context of acute ischemia-reperfusion injury following vascular surgery.

Engineering of cyanine-based nanoplatform with tunable response toward reactive species for ratiometric NIR-II fluorescent imaging in mice

High-quality second near-infrared (NIR-II) nanoprobes are of great significance for real-time bioimaging and medical diagnosis. Cyanine is an important class of fluorophores to construct activatable probes; however, there are still significant challenges hindering their biological applications, including weak fluorescence in aqueous solution, instability, and insufficient specificity. Herein, an integrated engineering strategy is conducted to develop the cyanine-based activatable NIR-II nanoplatforms with bright, stable emission and high specificity. Specifically, poly(styrene-co-maleic anhydride) (PSMA) is employed to encapsulate NIR-II fluorescent molecules (IR1048) to render the stable and bright NIR-II nanoparticles (PSMA@IR1048 NPs). By charge-modulated strategy, a series of cyanine-fluorophores are loaded on the surface of PSMA@IR1048 NPs and exhibit tunable response toward reactive species. Combing those two strategies, NIR-II ratiometric fluorescent nanoprobes (RNPs, including RNP1, RNP2, and RNP3) are constructed; among them, RNP2 displays hypochlorous acid (HClO) responsive performance and generates a higher NIR-II fluorescent ratio (FL2/FL1) signal. Such nanoprobe can reliably report the pathological HClO level in models of diabetic liver injury and lower limb ischemia–reperfusion (I/R) injury mice. Our study paves an engineering strategy to construct cyanine-based stable, bright, and specific NIR-II probes for bioimaging.

Syringic acid suppresses ferroptosis of skeletal muscle cells to alleviate lower limb ischemia/reperfusion injury in mice via the HMGB1 pathway.

Ischemia/reperfusion (I/R) of skeletal muscle in the lower limbs is an important factor affecting the outcome of lower limbs ischemia patients, with no effective preventive or therapeutic approaches available. The study was to investigate the effect of syringic acid (SA) on I/R skeletal muscle in the lower limbs injury. Mice femoral artery I/R models and C2C12 cell hypoxia/reoxygenation (H/R) models was establish, tissue damage, inflammatory status, and high mobility group box 1 (HMGB1) pathway were evaluated using histological analysis, enzyme-linked immunosorbent assay, and western blotting. Further, the study detected the effect of SA on cell apoptosis, lipid peroxidation, Fe2+ level, and ferroptosis-related proteins expression. Finally, the effect of HMGB1 expression on SA in H/R stimulation was studied. SA alleviated pathological damage and reduced levels of IL-1β, IL-6, and TNF-α in muscle tissues from femoral artery I/R mouse models. SA upregulated Bcl-2 and SOD as well as downregulated Bax, MDA, TBARS content, and Fe2+ level in H/R-induced cells. SA inhibited HMGB1 expression and promoted Nrf2, HO-1, GPX4, and SLC7A11 expressions in the injured tissues and cells. Such effects of SA on H/R-induced cells were rescued by HMGB1 overexpression. SA suppressed ferroptosis of skeletal muscle cells to alleviate lower limb I/R injury in mice by blocking the HMGB1 pathway, providing new insights for the treatment of lower limb ischemia-reperfusion injury.

The Prevention of Ischemia-Reperfusion Injury in Elderly Rats after Lower Limb Tourniquet Use.

Background: Lower limb ischemia-reperfusion injury (IRI-LL) is a common major complication of orthopedic surgery, especially in elderly patients. It has previously been demonstrated that folinic acid (FA) reduced IRI-LL damage in 3–4-month-old rats. This current work analyses the effect of FA in the prevention of IRI-LL in elderly animals. Methods: Forty-two 18-month-old male WAG/RijHsd rats were subjected to 3 h of ischemia. Eighteen animals received FA (2.5 mg/kg, ip) 20 min before the end of the ischemia period, while the other half received the same volume of saline solution. The animals were sacrificed after 3 h, 24 h, and 14 days of reperfusion for biochemical (tissue damage markers and electrolytes), histopathological studies of the gastrocnemius muscle and the daily assessment of the limb function by the Rota Rod test, respectively. Results: The administration of FA prior to the end of the ischemia period reduced the increase in LDH and CK observed in non-treated animals by 30–40% (p < 0.0001). When the histological sections were analyzed, FA was found to have reduced the number of damaged muscle fibers per field by 20% (60 ± 17.1 vs. 80.7 ± 16.4, p < 0.0001). The functional test revealed that FA also led to an improvement in the muscle function, assessed by the length of time that the animals kept running on the rod, compared to untreated animals. Conclusions: The administration of FA, prior to the end of the ischemic period, decreases the damage induced by IRI-LL, also achieving a faster recovery of mobility.

Deep Learning Reconstruction Algorithm-Based MRI Image Evaluation of Edaravone in the Treatment of Lower Limb Ischemia-Reperfusion Injury.

This research aimed to evaluate the therapeutic effect of edaravone on lower limb ischemia-reperfusion injury by MRI images of graph patch-based directional curvelet transform (GPBDCT), compression reconstruction algorithm. 200 patients with lower limb ischemia-reperfusion injury after replantation of severed limb were randomly divided into the observation group (edaravone treatment) and control group (Mailuoning injection treatment), with 100 cases in each group. MRI scanning and image processing using the GPBDCT algorithm were used to evaluate the therapeutic effect of the two groups of patients. The results showed that the signal noise ratio (SNR) (22.01), relative l2 norm error (RLNE) (0.0792), and matching degree γ (0.9997) of the compression and reconstruction algorithm based on GPBDCT were superior to those of the conventional compression and reconstruction algorithm (P < 0.05). MRI examination showed that the decrease of bleeding signal after treatment in the observation group was superior to that in the control group. The levels of superoxide dismutase (SOD) (15 ± 2.02), malondialdehyde (MDA) (2.27 ± 1.02), B cell lymphoma-2 (Bcl-2) (8.5 ± 1.02), Bcl-2-associated X (Bax) (3.7 ± 0.42), and Caspase-3 protein (35.9 ± 5.42) in the observation group before and after treatment were significantly higher than those in the control group (P < 0.05). In conclusion, the GPBDCT-based compression reconstruction algorithm has a better effect on MRI image processing, and edaravone can better remove free radicals and alleviate apoptosis.

Effects of Folinic Acid Administration on Lower Limb Ischemia/Reperfusion Injury in Rats.

Surgery under ischemic conditions, lasting up to 3 h, is routinely performed in orthopedic surgery, causing undesirable injury due to ischemia-reperfusion syndrome, with short and medium-term functional repercussions. To date, there is no established prophylactic treatment. In this work we evaluated folinic acid (FA) in a rodent model of lower limb ischemia-reperfusion (IRI-LL). 36 male WAG rats underwent 3 h of lower limb ischemia. In the saline group, rats received intraperitoneal administration of saline (used as vehicle for treatment). In the experimental group, rats were pretreated with FA (2.5 mg/kg) before the end of ischemia. After ischemia, animals were sacrificed at 3 h, 24 h or 14 days (for biochemical determination (Na+, K+, Cl-, urea, creatinine, CK, LDH, ALP, ALT, and AST), pathological assessment, or functional study using the rotarod test; respectively). Another six animals were used to establish the reference values. The prophylactic administration of FA significantly reduced the elevation of biochemical markers, especially those that most directly indicate muscle damage (CK and LDH). In addition, it also improved direct tissue damage, both in terms of edema, weight, PMN infiltrate and percentage of damaged fibers. Finally, the administration of FA allowed the animals to equal baseline values in the rotarod test; what did not occur in the saline group, where pre-ischemia levels were not recovered. Following 3 h of lower limb ischemia, FA minimizes the increase of CK and LDH, as well as local edema and leukocyte infiltration, allowing a faster recovery of limb functionality. Therefore, it could be considered as a prophylactic treatment when tourniquet is used in clinics.

Deleterious Effects of Remote Ischaemic Per-conditioning During Lower Limb Ischaemia–Reperfusion in Mice

The aim of this study was to investigate whether remote ischaemic per-conditioning might protect skeletal muscle during lower limb ischaemia-reperfusion (IR). Twenty-three male C57BL/6 mice were randomised into three groups: sham group (n= 7), IR group (unilateral tourniquet induced three hours of ischaemia followed by 24 hours of reperfusion, n= 8), and remote ischaemic per-conditioning group (RIPerC) (three cycles of 10 minute IR episodes on the non-ischaemic contralateral hindlimb, n= 8). Oxygraphy, spectrofluorometry, and electron paramagnetic resonance spectroscopy were performed in order to determine mitochondrial respiratory chain complexes activities, mitochondrial calcium retention capacity (CRC) and reactive oxygen species (ROS) production in skeletal muscle. IR impaired mitochondrial respiration (3.66 ± 0.98 vs. 7.31 ± 0. 54 μmol/min/g in ischaemic and sham muscles, p= .009 and p= .003 respectively) and tended to impair CRC (2.53 ± 0.32 vs. 3.64 ± 0.66 μmol/mg in ischaemic and sham muscles respectively, p= .066). IR did not modify ROS production (0.082 ± 0.004 vs. 0.070 ± 0.004 μmol/min/mg in ischaemic and sham muscles respectively, p= .74). RIPerC failed to restore mitochondrial respiration (3.82 ± 0.40 vs. 3.66 ± 0.98 μmol/min/g in ischaemic muscles from the RIPerC group and the IR group respectively, p= .45) and CRC (2.76 ± 0.3 vs. 2.53 ± 0.32 μmol/mg in ischaemic muscles from the RIPerC group and the IR group respectively, p= .25). RIPerC even impaired contralateral limb mitochondrial respiration (3.85 ± 0.34 vs. 7.31 ± 0. 54 μmol/min/g in contralateral muscles and sham muscles respectively, -47.3%, p= .009). RIPerC failed to protect ischaemic muscles and induced deleterious effects on the contralateral non-ischaemic muscles. These data do not support the concept of RIPerC.

The Effect of Hydrogen-Rich Saline Solution on Erythrocyte Deformability in Lower Limb Ischemia Reperfusion Injury in Rats

The Effect of Hydrogen-Rich Saline Solution on Erythrocyte Deformability in Lower Limb Ischemia Reperfusion Injury in Rats

Effects of dexmedetomidine on the function of distal organs and oxidative stress after lower limb ischaemia-reperfusion in elderly patients undergoing unilateral knee arthroplasty.

AimsThis study aims to evaluate the effects of dexmedetomidine on organ function, inflammation response, and oxidative stress in elderly patients following iatrogenic lower limb ischaemia–reperfusion (IR) during unilateral total knee arthroplasty.MethodsFollowing unilateral total knee arthroplasty, 54 elderly patients were randomized to receive either intraoperative intravenous injection of dexmedetomidine (n = 27) or equivalent volume of 0.9% saline (n = 27). Blood samples were harvested at 5 minutes before lower limb tourniquet release (baseline); and 1, 6 and 24 hours after tourniquet release. Surrogate markers of cardiac, pulmonary, hepatic and renal function, oxidative stress, inflammatory response, along with parasympathetic and sympathetic activity were recorded and analysed.ResultsThe levels of blood xanthine oxidase, creatine kinase, lactic acid and respiratory index increased in patients following tourniquet‐induced lower limb IR injury. Dexmedetomidine administration decreased the respiratory index (P = .014, P = .01, and P = .043) and the norepinephrine level (P < .001) at 1, 6 and 24 hours; and decreased the xanthine oxidase level (P = .049, P < .001) at 6 and 24 hours after tourniquet release compared with the Control group. Other measurements, including creatine kinase isoenzyme, lactate dehydrogenase, creatinine, urea nitrogen, glutamic–oxalacetic transaminase, glutamic–pyruvic transaminase, malondialdehyde, interleukin‐1, interleukin‐6 and tumour necrosis factor‐α, were not statistically significantly different between the 2 groups.ConclusionsIntraoperative dexmedetomidine administration in elderly patients dampens the deterioration in respiratory function and suppresses the oxidative stress response in elderly patients following iatrogenic lower limb IR injury.

Chloroquine ameliorates hind‐limb ischemia/reperfusion‐induced remote hepatic injury via attenuating p38‐Mapk/NF‐κB p65 cue

Lower limb ischemia-reperfusion (I/R) injury elicits systemic inflammation associated with multiple organ dysfunctions, a series of organ damage different from the initial insult. Chloroquine is an antimalarial drug that has been repurposed to manage a plethora of diseases, among which is rheumatoid arthritis, lupus erythematosus, and more recently Covide-19 based on its potent anti-inflammatory potential. This study aimed to investigate the effect of chloroquine as a treatment for the remote liver injury triggered by the hind-limb I/R insult. The experiment was conducted on three groups divided into control, hind-limb I/R induced by applying orthodontics rubber bands to one hind-limb for one and half hours followed by reperfusion for seven days, and chloroquine post-hind-limb I/R administration for seven days. Chloroquine protected the liver against the hind-limb I/R injury evident by decreasing the serum levels of the aminotransferases (ALT & AST) and deactivating the hepatic p38 mitogen-activated protein kinase (MAPK)/ nuclear factor (NF)-κB p65 cue to inhibit tumor necrosis factor-α with the elevation of interleukin-10 to verify its anti-inflammatory effect. Additionally, it readjusted redox imbalance indicated by the inhibition of nitric oxide, 8-hydroxy 2 deoxyguanosine, and malondialdehyde versus enhancing the total anti-oxidant capacity; also, the drug reduced caspase-3 and LC3 II. Accordingly, the present study showed that the chloroquine attenuates the hind-limb I/R-induced liver injury via its anti-inflammatory, anti-oxidant, and anti-apoptotic potentials mainly by deactivating the hepatic p38/p65 cue.

One Year on: Test Your Knowledge From January 2020

1. A rat model of acute lower limb ischemia reperfusion (I/R) investigated the effect of long non-coding RNA (lncRNA) DLGAP1 antisense RNA 1 (DLGAP1-AS1) silencing on vascular endothelial cell (VEC) injury via the PI3K/Akt pathway. Which of the following statements is correct?1A.Acute lower limb I/R increased the DLGAP1-AS1 expression in muscle tissues of rats.B.Acute lower limb I/R decreased the DLGAP1-AS1 expression in muscle tissues of rats.C.Acute lower limb I/R increased the DLGAP1-AS1 expression in VECs of rats.D.Acute lower limb I/R decreased the DLGAP1-AS1 expression in VECs of rats.E.None of the above.

N-asetil sistein alt ekstremite iskemi/ reperfüzyonu tarafından indüklenen feroptosise bağlı akciğer hasarını azaltır

Aim: This study aimed to analyze the effect of N-acetyl cysteine pretreatment on the prevention of ferroptosis mediated lung injury induced by lower limb ischemia and reperfusion. &#x0D; Material and Methods: Eighteen male Sprague-Dawley rats weighing 350-400 g were randomized into three groups. The animals received N-acetyl cysteine 150 mg/kg or normal saline 0.1 ml/kg intraperitoneally before the ischemic period. In the control and study groups, I/R injury was induced by clamping the aorta infrarenal for 2 hours, followed by 4 hours of reperfusion. The third group underwent sham surgery. After sacrifice, the lungs of the animals were extracted for both histopathological and biochemical analysis. &#x0D; Results: There was a significant difference between the control and study animals regarding tissue malondialdehyde (MDA), and glutathione (GSH) levels. In the control group, the MDA levels were increased and the GSH levels were increased significantly compared to the sham group that revealed a ferroptosis mediated lung injury. However, N-acetyl cysteine decreased the levels of MDA and increased the levels of GSH revealing a protective effect. The Prussian blue (free iron stain) staining which was used to examine iron deposition revealed a reduced deposition of iron in the N-acetyl cysteine group. &#x0D; Conclusion: The results of the present study suggest a protective effect of N-acetyl cysteine on ferroptosis mediated lung injury induced by lower limb ischemia-reperfusion in a rat model.

Effects of alpha-lipoic acid on skeletal muscle ischemia-reperfusion injury in mice

Aim: The main problem in the treatment of cardiovascular diseases, which is the most common cause of death in the world today, is reperfusion injury. In our study, we investigated the effects of alpha-lipoic acid on lower limb ischemia-reperfusion injury. Methods: In this study, 30 male Swiss breed albino mice weighing 45-65 g were used. Mice were randomly divided into 5 groups (Control group (C), Dimethyl Sulfoxide (DMSO) group, ischemia-reperfusion (IR) group, alpha-lipoic acid control group (ALA), alpha-lipoic acid - IR group (ALA+IR)), 6 mice in each group. All groups were administered 100 IU/kg intravenous heparin bolus 30 minutes before the procedure. Lower limb ischemia (2 hours) and reperfusion (2 hours) protocols were applied to the IR and ALA+IR groups by clamping the main femoral artery. Alpha-lipoic acid was administered to ALA and ALA+IR groups 1 hour before the experimental procedure (100 mg/kg intraperitoneal). After the experiment protocol, the lower limb gastrocnemius muscles were collected from the sacrificed mice and total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), Myeloperoxidase (MPO) and Malondialdehyde (MDA) levels were determined in the tissue. In addition, edema, necrosis, and inflammatory cell infiltration levels in the skeletal muscle were determined by histologic grading, and apoptosis was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. Results: TAS measurements of ALA group subjects were higher than the control group (P=0.01). The TOS level of the ALA+IR group was lower than the IR group (P=0.01), but higher than the C, ALA, and DMSO groups. The OSI index of the IR group was significantly higher than the ALA+IR group (P=0.01). It was observed that the IR group was at higher levels than the ALA+IR group (P=0.01). MDA measurements of IR group subjects were higher than that of the C, ALA, DMSO, ALA+IR groups (P=0.01). Edema of the IR and ALA+IR group subjects were higher than the C, ALA, DMSO groups (P=0.01). Necrosis measurements of IR and ALA+IR group subjects were higher than C, ALA, DMSO groups (P=0.01). Inflammatory cell infiltration measurements of IR and ALA+IR group subjects were higher than C, ALA, DMSO groups (P=0.01). Apoptosis level was significantly lower in the ALA+IR group than in the IR group. (P=0.01). Conclusion: The results showed us that alpha-lipoic acid has a protective effect against oxidative damage, inflammation, and apoptosis in the tissue in lower limb ischemia-reperfusion.

Hyperspectral Imaging Quantification of Mouse Limb Microcirculation Using an Ischemia Reperfusion Model with Phosphodiesterase 5 Inhibitor Preconditioning.

Background: Peripheral arterial disease has high incidence and complication rates. Vessel recanalization represents the main therapy. However, it induces reperfusion injury. Preconditioning with sildenafil has been advocated to protect against this injury. In this study, we show a real-time noninvasive quantitative assessment using hyperspectral imaging (HSI) of ischemia/reperfusion (IR) and analyzing the sildenafil effect. Materials and Methods: A one-sided hindlimb ischemia (120 minutes) followed by reperfusion (30 minutes) was created. Five mice received Sildenafil (1 mg/kg, i.p. twice before ischemia) and 5 mice served as control. The StO2 at T0, 5, 30, 60, 120 minutes after ischemia (T5, 30, 60, 120) and 5, 15, and 30 minutes after reperfusion (T125, 135, 150) were measured through HSI. Results: The control group showed a significantly lower StO2 at T120 (24.8% ± 17%) as compared with T0 (53.3% ± 7.04%) (P = .013) and T150 (76.8 ± 3.77; P = .0008). T150 showed a statistically significantly higher StO2 than T0 (P = .0134). In the sildenafil group, T120 StO2 (28.6% ± 20%) was lower than T0 (63.3% ± 8.46%; P = .0312) and T150 (73.3% ± 19.1%, P = .0075). The StO2 values did not differ statistically between sildenafil and control groups. Conclusions: HSI is a feasible tool to quantify both ischemia and reperfusion phases during lower limb IR. Preconditioning with sildenafil did not modify IR-related StO2 changes.

The effect of fullerenol C60 on skeletal muscle after lower limb ischemia reperfusion injury in streptozotocin-induced diabetic rats

Aim: Fullerenol, a water-soluble C60-fullerene, has been demonstrated to scavenge free radicals in vitro and in vivo. The aim of the study was to investigate the effects of fullerenol C60 on lower skeletal muscles in a rat model of ischemia/reperfusion (I/R).Methods: After approval of the ethics committee, 30 Wistar Albino rat were divided into 5 groups with six animals per each as follows: Control (C), diabetes (D), diabetes+fullerenol C60 (DF), diabetes+I/R (group DIR) and diabetes I/R+fullerenol C60 (DIR-F) groups. Streptozotocin was administered to the rats to induce diabetes at a dose of 55 mg/kg. Four weeks after the onset of diabetes, rats were subjected to 2 hours of ischemia and 2 hours of reperfusion. At the end of the reperfusion period, skeletal muscle samples were taken from the lower extremity in all groups for histopathological and immunohistopathological examinations. Results: Myositis and endothelial caspase 3 enzyme activities were high in all groups, particularly DIR. Compared to C, DF and DIR-F groups, inflammation and myositis were significantly higher in the DIR group (P=0.001, P=0.006, P=0.001, respectively, and P=0.001, P=0.022, P=0.001, respectively). Vascular dilatation and congestion were significantly more prominent in all groups compared to the control group (P=0.001 for all).Conclusion: Our results confirm that fullerenol C60 has protective effects against skeletal muscle damage resulting from I/R in diabetic rats. Future studies conducted to evaluate these effects may help illuminate the action mechanism of fullerenol C60 and pathophysiology underlying the tissue damage related to I/R injury.

How important is the damage to the liver after lower limb ischemia-reperfusion? An experimental study in a rat model.

The aim of this study was to compare the effect of lower extremity ischemia reperfusion on the liver and the effect of ischemiareperfusion on the liver itself in a rat model. Thirty Sprague-Dawley male rats were randomly divided into three groups including 10 in each group: sham (Group 1), lower limb ischemia-reperfusion (Group 2), and liver ischemia-reperfusion (Group 3). In Group 2, one hour of left lower limb ischemia was performed. In Group 3, one hour of ischemia in the liver was performed, followed by 24 hours of reperfusion. After reperfusion, the liver tissues were removed, and the groups were evaluated biochemically and histologically. The liver malondialdehyde levels were significantly higher in Groups 2 and 3 than in the sham group (p<0.001). In Group 2, the malondialdehyde levels were significantly higher than in Group 3 (p=0.019). The glutathione levels in the liver were significantly lower in Groups 2 and 3 than in the sham group (p<0.001). However, the glutathione levels were significantly higher in Group 2 than in Group 3 (p=0.005). In the histological evaluation, although the liver damage score was higher in Group 3 than in Group 2 (p=0.015), there was no significant difference between the two groups in TUNEL(+) cell number (p>0.05). Reperfusion injury in the liver after lower limb ischemiareperfusion is as important as ischemia-reperfusion injury which is specifically induced in the liver. This should be taken into account, particularly in reperfusion surgeries following vascular trauma or in cases of leg tourniquets to stop bleeding after lower limb vascular trauma.